Conventional x-ray collimators are typically constructed for shaping x-ray beams. Usually, conventional collimators include beam blocking leaves made of x-ray attenuating materials that have high atomic number (high-Z material). In most cases, the collimator beam blocking leaves cut out portions of the beam that are not useful for diagnostic, guidance, or therapy purposes. The collimator leaves are either manually moved or motorized with some systems allowing control over the motion of individual leaves for shrinking or expanding the x-ray field of view. However, conventional collimators have not been designed to modulate the beam quality of an x-ray beam such as the beam energy, intensity, or dose distribution.
Accordingly, there is a need for a collimator device that can be used to modify the beam quality and the shape and size of a beam. There is a need for a radiation apparatus in which the operation of the x-ray source and the collimator device can be synchronized such that the modification of the beam quality, shape, or size of a beam can be substantially in real time with the generation of the beam.